如何获取没有最后 N 个字符的字符串？

Question

如果我的变量中有一个 bash 字符串。如何提取/检索除最后一个字符之外的字符串，如果我想提取直到最后两个字符，会有多容易？

例子：

# Removing the last character
INPUT="This is my string."
# Expected output "This is my string"

# Removing the last two characters
INPUT="This is my stringoi"
# Expected output "This is my string"

Answer 1

对于任何 POSIX shell：

OUTPUT="${INPUT%?}"  # remove last character
OUTPUT="${INPUT%??}" # remove last two characters
                     # and so on

Answer 2

样本：

INPUT="This is my string."
echo $INPUT |sed 's/.$//' # removes last character

INPUT="This is my stringoi"
echo $INPUT |sed 's/..$//' # removes last two character